GUWAHATI, India -- At least 100 people were injured when anti-government protestors clashed overnight with security forces in India's riot-torn northeastern state of Manipur, officials said Monday.

Manipur Police Chief A.S. Siddiqui said up to 30,000 protestors defied a shoot-on-sight curfew late Sunday night in the state capital Imphal, burning tyres and pelting stones at government residences and security patrols.

"Troops fired teargas and fired in the air to disperse the crowd," the police chief told AFP by telephone from Imphal. "The situation is tense", he added.

Witnesses said paramilitary soldiers baton-charged the protestors and fired rubber bullets, injuring more than 100 people.

"The security forces also took injuries," Siddiqui said.

Manipur has been hit by violent protests, in which at least 19 people have been killed, since New Delhi last month extended a ceasefire with a faction of the outlawed National Socialist Council of Nagaland (NSCN).

Under the extension, the ceasefire is to be implemented across India and not just in the province of Nagaland.

The broadening of the ceasefire triggered fears that New Delhi might be considering carving slices off the neighboring states of Arunachal Pradesh, Assam, and Manipur -- all with sizeable Naga populations -- to create a greater Nagaland.

In neighboring Assam State, NSCN rebels were believed to be responsible for an ambush on a paramilitary police convoy that killed three and wounded two more late Sunday night.

The latest clashes in Manipur, which borders Myanmar, came as a 24-hour general strike began across the state at midnight Sunday.